By Dr. Gary L. Deel, Ph.D., J.D.
Faculty Director, School of Business, American Public University
As the title of this series suggests, modern human societies have effectively halted human evolution by natural selection. Now we’ll look at how this has happened and what it means for the future.
Let’s begin by pondering some of the natural forces that might have — in generations long gone before modern societies existed — prevented a person from reaching productive age and having children. These forces would have included weather and other natural disasters, diseases, dangerous predators, and accidents.
The advent of modern society, however, drastically reduced fatalities from these threats. With modern weather tracking and natural disaster warning systems, few people today die from hurricanes and floods. A sophisticated infrastructure today means people no longer have to hunt in the wild for food. And control of wildlife means hardly anyone dies from animal attacks today.
Also, while accidents do still happen all the time, our excellent doctors and hospitals are often able to treat wounds and injuries that once were fatal. And likewise, modern medicine has found cures or treatments for all but the most stubborn and resilient diseases.
For example, the epidemic that ravaged Athens around 430 BC lasted for five years, according to Live Science. Some estimates put the death toll as high as 100,000 people.
Then there was the Black Death plague in the middle of the 14th century which was thought to have originated in Asia. Live Science notes, “Some estimates suggest that it wiped out over half of Europe’s population. It was caused by a strain of the bacterium Yersinia pestis that is likely extinct today and was spread by fleas on infected rodents.”
Medical, Technological, and Industrial Innovations Save Most People
Of course, humans still die from all of these causes today. A case in point would be our struggle to contain the current COVID-19 pandemic.
However, it’s obvious that our modern scientific understanding and practices are minimizing losses that could have otherwise been as catastrophic as the diseases of ancient history. The medical, technological, and industrial powers today allow us to save all but the smallest fraction of unfortunate cases. And of those relatively few who do die today, not all of them succumb before reaching sexual maturity.
For example, some types of cancer tragically attack children and may claim lives before they reach adulthood and can start families of their own. But fatalities from hurricanes, tornadoes, car and plane accidents, shark attacks, snake bites, and other causes of death generally do not disproportionately affect younger populations, so natural selection is not in play in these cases.
So what does this all mean? It means that evolution by natural selection is becoming less and less relevant to the human condition in the 21st century. To be fair, there may still be natural forces in play that affect the forward trajectory of human gene diversity.
The Vast Majority of Natural Forces No Longer Threaten Our Ability to Procreate
As mentioned earlier, diseases that cause pre-puberty mortality that are either genetically induced or that affect individuals with certain genetic variants may still shape the gene pool. That is, at least until we are able to cure or treat these variants as we have already done with so many diseases. But for the vast majority of natural forces, we have sufficiently conquered them so they no longer threaten our ability to procreate and pass on our DNA.
This is obviously a good thing and an achievement to be celebrated in terms of lives saved or at least prolonged as a direct result of innovation and progress. But this also signals a very interesting future for us, the first species that has to a large extent inoculated itself against evolution by natural selection.
Our genetic material will of course continue to change and evolve as subsets of the species birth offspring with unique characteristics. But we will no longer be at the mercy of the environment as we were for millions of years.
The ability to overcome Mother Nature in this sense is a tremendous accomplishment. Let us just hope we live up to the mantle of a species with this unique capability.
About the Author
Dr. Gary Deel is a Faculty Director with the School of Business at American Public University. He holds a J.D. in Law and a Ph.D. in Hospitality/Business Management. Gary teaches human resources and employment law classes for American Public University, the University of Central Florida, Colorado State University and others.